Direct determination of thermal conductivity of solids and liquids at verylow frequencies using the photopyroelectric method

In this work we show that, besides thermal effusivity, thermal diffusivity and heat capacity, the thermal conductivity can be determined directly, usi ng the photopyroelectric method. We have developed a theoretical frame for the direct thermal conductivity measurement with the FPPE method and we hav e illustrated its practical feasibility by applying it to liquid and solid samples. The obtained results are in agreement with literature values.